A sensor element device is known from EP 859 467 A (also published as U.S. Pat. No. 5,917,165), having a voluminous and spatial-shape-variable plastic body in cylindrical form with a recess in the longitudinal direction. On its upper side, a plastic disk having a translucent portion in symbol form, for example as an elongated rectangle, is provided. An LED provided inside the recess in the plastic body therefore has the effect of creating an illuminated symbol display. The upper side of the elastic plastic body as a wide circular ring forms a capacitive sensor element of the capacitive proximity switch device.
It is furthermore known from EP 1 030 536 A1 (also published as U.S. Pat. No. 6,403,904) how to provide a surrounding metal frame with an illuminated display as a seven-segment display. This frame runs supported at the side past the illuminated display and thereby, as it were, enables a capacitive proximity switch to be created with an illuminated display. If a finger is placed on the illuminated display, in particular with an operating panel in between them, the capacitive proximity switch can detect this and trigger a switching function.